I'm wondering if the ratio between deadlift volume and max acts as any sort of diagnostic.

My "sorta max" DL is somewhere around 265-270. Today I did 10 sets of 3 at 235 in about 20 minutes. This wasn't a max test by any means; I just wanted to see how long it would take to do 10 triples with comfortable rest periods. Does this mean anything useful? Bodyweight is about 150-155, and I usually only deadlift once every 10-12 days.

Jay I am sure there are all scientific formulas for predicting 1Rmax based on other reps such as 3..5...8..10, but those are best guess as all our muscle fiber makeups are different....for example someone may be great at lower reps and heavy weight....doesn't mean they can pound out 50% at high reps.....and the reverse...you may be great at a low weight for 15 reps...but that may not lineraly correspond to a 1Rmax. In the end you will see your strength go up as long as you are progressing in volume per session, whether that be more reps per set or more weight. Of course rest periods play into the volume potential too as you will be stronger with longer rests.

In general...any reps done between 1-10 will increase strength.....reps 1-5 increase the most strength...however you still get added strength benefits in doing reps 6-10. In total volume work, if you do somewhere in the range of 20-30reps it's more strength.....30-50 will also have some strength but is leaning more towards hypertrophy.